Food products are often mixed in the container of a blender or food processor. A cover or lid, which is often made of a flexible rubber-like material, is placed on the container, and blades positioned in the bottom of the container mix the food, at least a portion of which is a liquid material. At times, particularly when the container is nearly full of a liquid material, the agitation of the blades causes the liquid to swirl which could result in a great deal of turbulence in the container. Such turbulence can cause the container to rock or sway and can cause the cover to undulate. If allowed to continue, such could result in the container actually falling off of the base of the blender or the cover coming loose from the container allowing the contents to spill out of the container.